Commit c35ecb95 authored by Joanne Koong's avatar Joanne Koong Committed by Jakub Kicinski
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selftests/net: Add test for timing a bind request to a port with a populated bhash entry 



This test populates the bhash table for a given port with
MAX_THREADS * MAX_CONNECTIONS sockets, and then times how long
a bind request on the port takes.

When populating the bhash table, we create the sockets and then bind
the sockets to the same address and port (SO_REUSEADDR and SO_REUSEPORT
are set). When timing how long a bind on the port takes, we bind on a
different address without SO_REUSEPORT set. We do not set SO_REUSEPORT
because we are interested in the case where the bind request does not
go through the tb->fastreuseport path, which is fragile (eg
tb->fastreuseport path does not work if binding with a different uid).

To run the script:
    Usage: ./bind_bhash.sh [-6 | -4] [-p port] [-a address]
	    6: use ipv6
	    4: use ipv4
	    port: Port number
	    address: ip address

Without any arguments, ./bind_bhash.sh defaults to ipv6 using ip address
"2001:0db8:0:f101::1" on port 443.

On my local machine, I see:
ipv4:
before - 0.002317 seconds
with bhash2 - 0.000020 seconds

ipv6:
before - 0.002431 seconds
with bhash2 - 0.000021 seconds

Signed-off-by: default avatarJoanne Koong <joannelkoong@gmail.com>
Signed-off-by: default avatarJakub Kicinski <kuba@kernel.org>
parent 28044fc1

tools/testing/selftests/net/.gitignore

+2 −1
Original line number Diff line number Diff line
@@ -40,3 +40,4 @@ tun 
cmsg_sender

unix_connect

tap

bind_bhash

tools/testing/selftests/net/Makefile

+3 −0
Original line number Diff line number Diff line
@@ -43,6 +43,7 @@ TEST_PROGS += ndisc_unsolicited_na_test.sh 
TEST_PROGS += arp_ndisc_untracked_subnets.sh

TEST_PROGS += stress_reuseport_listen.sh

TEST_PROGS := l2_tos_ttl_inherit.sh

TEST_PROGS += bind_bhash.sh

TEST_PROGS_EXTENDED := in_netns.sh setup_loopback.sh setup_veth.sh

TEST_PROGS_EXTENDED += toeplitz_client.sh toeplitz.sh

TEST_GEN_FILES =  socket nettest
@@ -64,6 +65,7 @@ TEST_GEN_FILES += cmsg_sender 
TEST_GEN_FILES += stress_reuseport_listen

TEST_PROGS += test_vxlan_vnifiltering.sh

TEST_GEN_FILES += io_uring_zerocopy_tx

TEST_GEN_FILES += bind_bhash



TEST_FILES := settings
@@ -74,3 +76,4 @@ include bpf/Makefile 
$(OUTPUT)/reuseport_bpf_numa: LDLIBS += -lnuma

$(OUTPUT)/tcp_mmap: LDLIBS += -lpthread

$(OUTPUT)/tcp_inq: LDLIBS += -lpthread

$(OUTPUT)/bind_bhash: LDLIBS += -lpthread

tools/testing/selftests/net/bind_bhash.c

0 → 100644
+144 −0
Original line number Diff line number Diff line 
// SPDX-License-Identifier: GPL-2.0

/*

 * This times how long it takes to bind to a port when the port already

 * has multiple sockets in its bhash table.

 *

 * In the setup(), we populate the port's bhash table with

 * MAX_THREADS * MAX_CONNECTIONS number of entries.

 */



#include <unistd.h>

#include <stdio.h>

#include <netdb.h>

#include <pthread.h>

#include <string.h>

#include <stdbool.h>



#define MAX_THREADS 600

#define MAX_CONNECTIONS 40



static const char *setup_addr_v6 = "::1";

static const char *setup_addr_v4 = "127.0.0.1";

static const char *setup_addr;

static const char *bind_addr;

static const char *port;

bool use_v6;

int ret;



static int fd_array[MAX_THREADS][MAX_CONNECTIONS];



static int bind_socket(int opt, const char *addr)

{

	struct addrinfo *res, hint = {};

	int sock_fd, reuse = 1, err;

	int domain = use_v6 ? AF_INET6 : AF_INET;



	sock_fd = socket(domain, SOCK_STREAM, 0);

	if (sock_fd < 0) {

		perror("socket fd err");

		return sock_fd;

	}



	hint.ai_family = domain;

	hint.ai_socktype = SOCK_STREAM;



	err = getaddrinfo(addr, port, &hint, &res);

	if (err) {

		perror("getaddrinfo failed");

		goto cleanup;

	}



	if (opt) {

		err = setsockopt(sock_fd, SOL_SOCKET, opt, &reuse, sizeof(reuse));

		if (err) {

			perror("setsockopt failed");

			goto cleanup;

		}

	}



	err = bind(sock_fd, res->ai_addr, res->ai_addrlen);

	if (err) {

		perror("failed to bind to port");

		goto cleanup;

	}



	return sock_fd;



cleanup:

	close(sock_fd);

	return err;

}



static void *setup(void *arg)

{

	int sock_fd, i;

	int *array = (int *)arg;



	for (i = 0; i < MAX_CONNECTIONS; i++) {

		sock_fd = bind_socket(SO_REUSEADDR | SO_REUSEPORT, setup_addr);

		if (sock_fd < 0) {

			ret = sock_fd;

			pthread_exit(&ret);

		}

		array[i] = sock_fd;

	}



	return NULL;

}



int main(int argc, const char *argv[])

{

	int listener_fd, sock_fd, i, j;

	pthread_t tid[MAX_THREADS];

	clock_t begin, end;



	if (argc != 4) {

		printf("Usage: listener <port> <ipv6 | ipv4> <bind-addr>\n");

		return -1;

	}



	port = argv[1];

	use_v6 = strcmp(argv[2], "ipv6") == 0;

	bind_addr = argv[3];



	setup_addr = use_v6 ? setup_addr_v6 : setup_addr_v4;



	listener_fd = bind_socket(SO_REUSEADDR | SO_REUSEPORT, setup_addr);

	if (listen(listener_fd, 100) < 0) {

		perror("listen failed");

		return -1;

	}



	/* Set up threads to populate the bhash table entry for the port */

	for (i = 0; i < MAX_THREADS; i++)

		pthread_create(&tid[i], NULL, setup, fd_array[i]);



	for (i = 0; i < MAX_THREADS; i++)

		pthread_join(tid[i], NULL);



	if (ret)

		goto done;



	begin = clock();



	/* Bind to the same port on a different address */

	sock_fd  = bind_socket(0, bind_addr);

	if (sock_fd < 0)

		goto done;



	end = clock();



	printf("time spent = %f\n", (double)(end - begin) / CLOCKS_PER_SEC);



	/* clean up */

	close(sock_fd);



done:

	close(listener_fd);

	for (i = 0; i < MAX_THREADS; i++) {

		for (j = 0; i < MAX_THREADS; i++)

			close(fd_array[i][j]);

	}



	return 0;

}

tools/testing/selftests/net/bind_bhash.sh

0 → 100755
+66 −0
Original line number Diff line number Diff line 
#!/bin/bash

# SPDX-License-Identifier: GPL-2.0



NR_FILES=32768

SAVED_NR_FILES=$(ulimit -n)



# default values

port=443

addr_v6="2001:0db8:0:f101::1"

addr_v4="10.8.8.8"

use_v6=true

addr=""



usage() {

    echo "Usage: $0 [-6 | -4] [-p port] [-a address]"

    echo -e "\t6: use ipv6"

    echo -e "\t4: use ipv4"

    echo -e "\tport: Port number"

    echo -e "\taddress: ip address"

}



while getopts "ha:p:64" opt; do

    case ${opt} in

	h)

	    usage $0

	    exit 0

	    ;;

	a)  addr=$OPTARG;;

	p)

	    port=$OPTARG;;

	6)

	    use_v6=true;;

	4)

	    use_v6=false;;

    esac

done



setup() {

    if [[ "$use_v6" == true ]]; then

	ip addr add $addr_v6 nodad dev eth0

    else

	ip addr add $addr_v4 dev lo

    fi

	ulimit -n $NR_FILES

}



cleanup() {

    if [[ "$use_v6" == true ]]; then

	ip addr del $addr_v6 dev eth0

    else

	ip addr del $addr_v4/32 dev lo

    fi

    ulimit -n $SAVED_NR_FILES

}



if [[ "$addr" != "" ]]; then

    addr_v4=$addr;

    addr_v6=$addr;

fi

setup

if [[ "$use_v6" == true ]] ; then

    ./bind_bhash $port "ipv6" $addr_v6

else

    ./bind_bhash $port "ipv4" $addr_v4

fi

cleanup